If you take a look at the console of your OVM servers, they should print the former UUID on the screen right below the local hostname. If the screen is blanked, hit the shift key. The manager UUID is usually printed on the "splash screen" of any of my OVM servers...

Also, if you print the contents of this file on any of your OVMS: /etc/ovs-agent/db/server, you will find something like this: